Electronic Spectroscopy of Atomic Defects in Molybdenum Disulfide under Ambient Conditions

We present results of electronic spectroscopy experiments performed on individual defects in the prototypical transition metal dichalcogenide (TMD) molybdenum disulfide (MoS2) under ambient conditions by way of conductive atomic force microscopy (C-AFM). Data acquired in the form of consecutive, high-resolution current maps at various bias voltages allow the assessment of local conductivity and differential conductance as a function of bias voltage for individual defects, the effects of which range from single-atomic sites to several nanometers in lateral size. Characteristic behavior in spectroscopy data allows the categorization of observed defects into distinct groups and provides clues with regard to their chemical identities.